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How to calculate resistance and capacitance when LED uses 220 V If you want to make LED lamp (48 lamp caps and other lamp caps), the teacher will tell you how to calculate the resistance and capacitance under 220 V, and what the formula is. Please be more detailed Led parallel
I've been working on LED lamps for more than 2 years. I'll give you the capacitance and resistance data of 48 bead resistance and capacitance power supply directly. This is the data obtained from years of practice, which is more accurate than the formula calculation
Step down capacitor: CBB capacitor 474j / 400V
Current limiting resistor: 1W carbon film resistor 360-470 Ω
Current: about 15-16ma
How much resistance should be used to reduce the voltage of 220 V to about 10 V?
I've changed alternating current into direct current. Please help me to calculate the formula. Thank you
This is known according to the formula! As long as you know the working current you need! You can know how big your resistance needs! The resistance multiplied by the current value will get the voltage! 220V = resistance value x current value + 10x current value, but I suggest you read the relevant books first! This is not a joke!
For voltage calculation, I would like to ask the following question: jumper resistor 1 + capacitor + resistor 2 on AC 220 V voltage (resistor 1 = 56 pairs, capacitor = 0.1 UF; resistor 2 = 300 pairs)
I would like to ask how much voltage can be measured on resistor 2 when the above circuit is connected, and how much voltage can be measured if resistor 2 is disconnected? Please answer patiently,
"The three are all connected in series, and then connected with 220 v. but the problem is that if R2 is removed, 220 V can be measured in the open circuit measurement, but after adding it, the voltage at both ends of R2 immediately drops to a few tenths of a volt, so I feel a little puzzled" -- I don't know what to say on the first floor, Of course, the voltage at both ends of R2 is a few tenths of a volt immediately
(plus points) when a capacitor and a resistor are connected to a 220 V AC power supply, it is known that the voltage drop on the resistor is 120 V, so the voltage on the capacitor is?
Normally.
The power supply voltage is u = 220 v,
Voltage on resistor ur = 120V
Let the voltage of capacitor be UC
UC = (U × u-ur × ur) ^ (1 △ 2) = 184.39v
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